Frame

Numbered 30940 to 36442 (approx). Bolt on seat stays with drawback type chainstays for rear wheel adjustment.

Wheels

WM1x21 (f), WM1x21 (r), interchangeable with black enamelled rims. Black spokes with NPB nipples. Bolt on sprocket.

Mudguards

5” D section, both unvalanced. Rear with detachable tail piece with 4” mudguards as an option.

Tanks

Petrol tank black with gold lined panels. Single offset Westwood type filler with front fitted petrol balance pipe. Single bolt damper arm fixing and side cut away for sparking plug access. Brass lever petrol tap.  Rounded oil tank mounted on seat tube with single Westwood type filler to offside. Oil tank fitted with hand cable operated auxiliary oil pump with pipe to rear of crankcase. Rear cylinder feed from pump.

Engine

Numbered 52000 to 57000 (approx) - 4 valve 499cc with iron open valve parallel inlet & parallel exhaust cylinder head. 18mm CENTRAL plug but with retained side plug fitting (blanked off). Forward mounted 6V ML Maglita or round ML magneto. Sandblasted crankcases. Rockers supported in large nuts in rocker plates bolted to the cylinder head. Square based cylinder barrel and webbed (6) drive side crankcase with central circular web. Total loss oiling with vertical adjustable ‘pump’ in timing cover. Cast alloy ‘oval’ rocker box. 3 main bearings.

Brakes

8” front and rear, coupled with steel shoes.

Electrics (optional)

Miller 6” 64EA headlamp (with small ammeter retained by 3 screws), rear mounted switch and 34E rear lamp.

Transmission

4 speed semi-close ratio gearbox with hand change on RHS. External kickstarter stop. Aluminium non-oil bath chain cover with aluminium chainguard.

Carburetter

Amac type 10MDY (1.3/32”) with 2 lever control (optional twist grip).

Exhaust system

Twin 1 3/4” low level pipes into Rudge ‘can’ type silencers and 6” fishtails. Pipes fitted OVER cast in cylinder head exhaust stubs.

Standard Fittings

1” handlebars with folded type inverted levers and Rudge steering damper. Spanner adjusted fork shock absorber. Single leather fronted toolbox fitted to nearside of machine above rear wheel. Riveted angle & strip steel centre stand. Open ended ‘D’ section forks.

Extras

None listed.

©  Colin Chapple